--- /dev/null
+/*
+ * Copyright (c) 2008, 2009 Nicira Networks.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <config.h>
+#include "stream-ssl.h"
+#include "dhparams.h"
+#include <assert.h>
+#include <ctype.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <string.h>
+#include <netinet/tcp.h>
+#include <openssl/err.h>
+#include <openssl/ssl.h>
+#include <openssl/x509v3.h>
+#include <poll.h>
+#include <sys/fcntl.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include "dynamic-string.h"
+#include "leak-checker.h"
+#include "ofpbuf.h"
+#include "openflow/openflow.h"
+#include "packets.h"
+#include "poll-loop.h"
+#include "socket-util.h"
+#include "socket-util.h"
+#include "util.h"
+#include "stream-provider.h"
+#include "stream.h"
+
+#include "vlog.h"
+#define THIS_MODULE VLM_stream_ssl
+
+/* Active SSL. */
+
+enum ssl_state {
+ STATE_TCP_CONNECTING,
+ STATE_SSL_CONNECTING
+};
+
+enum session_type {
+ CLIENT,
+ SERVER
+};
+
+struct ssl_stream
+{
+ struct stream stream;
+ enum ssl_state state;
+ int connect_error;
+ enum session_type type;
+ int fd;
+ SSL *ssl;
+ struct ofpbuf *txbuf;
+
+ /* rx_want and tx_want record the result of the last call to SSL_read()
+ * and SSL_write(), respectively:
+ *
+ * - If the call reported that data needed to be read from the file
+ * descriptor, the corresponding member is set to SSL_READING.
+ *
+ * - If the call reported that data needed to be written to the file
+ * descriptor, the corresponding member is set to SSL_WRITING.
+ *
+ * - Otherwise, the member is set to SSL_NOTHING, indicating that the
+ * call completed successfully (or with an error) and that there is no
+ * need to block.
+ *
+ * These are needed because there is no way to ask OpenSSL what a data read
+ * or write would require without giving it a buffer to receive into or
+ * data to send, respectively. (Note that the SSL_want() status is
+ * overwritten by each SSL_read() or SSL_write() call, so we can't rely on
+ * its value.)
+ *
+ * A single call to SSL_read() or SSL_write() can perform both reading
+ * and writing and thus invalidate not one of these values but actually
+ * both. Consider this situation, for example:
+ *
+ * - SSL_write() blocks on a read, so tx_want gets SSL_READING.
+ *
+ * - SSL_read() laters succeeds reading from 'fd' and clears out the
+ * whole receive buffer, so rx_want gets SSL_READING.
+ *
+ * - Client calls stream_wait(STREAM_RECV) and stream_wait(STREAM_SEND)
+ * and blocks.
+ *
+ * - Now we're stuck blocking until the peer sends us data, even though
+ * SSL_write() could now succeed, which could easily be a deadlock
+ * condition.
+ *
+ * On the other hand, we can't reset both tx_want and rx_want on every call
+ * to SSL_read() or SSL_write(), because that would produce livelock,
+ * e.g. in this situation:
+ *
+ * - SSL_write() blocks, so tx_want gets SSL_READING or SSL_WRITING.
+ *
+ * - SSL_read() blocks, so rx_want gets SSL_READING or SSL_WRITING,
+ * but tx_want gets reset to SSL_NOTHING.
+ *
+ * - Client calls stream_wait(STREAM_RECV) and stream_wait(STREAM_SEND)
+ * and blocks.
+ *
+ * - Client wakes up immediately since SSL_NOTHING in tx_want indicates
+ * that no blocking is necessary.
+ *
+ * The solution we adopt here is to set tx_want to SSL_NOTHING after
+ * calling SSL_read() only if the SSL state of the connection changed,
+ * which indicates that an SSL-level renegotiation made some progress, and
+ * similarly for rx_want and SSL_write(). This prevents both the
+ * deadlock and livelock situations above.
+ */
+ int rx_want, tx_want;
+};
+
+/* SSL context created by ssl_init(). */
+static SSL_CTX *ctx;
+
+/* Required configuration. */
+static bool has_private_key, has_certificate, has_ca_cert;
+
+/* Ordinarily, we require a CA certificate for the peer to be locally
+ * available. 'has_ca_cert' is true when this is the case, and neither of the
+ * following variables matter.
+ *
+ * We can, however, bootstrap the CA certificate from the peer at the beginning
+ * of our first connection then use that certificate on all subsequent
+ * connections, saving it to a file for use in future runs also. In this case,
+ * 'has_ca_cert' is false, 'bootstrap_ca_cert' is true, and 'ca_cert_file'
+ * names the file to be saved. */
+static bool bootstrap_ca_cert;
+static char *ca_cert_file;
+
+/* Who knows what can trigger various SSL errors, so let's throttle them down
+ * quite a bit. */
+static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(10, 25);
+
+static int ssl_init(void);
+static int do_ssl_init(void);
+static bool ssl_wants_io(int ssl_error);
+static void ssl_close(struct stream *);
+static void ssl_clear_txbuf(struct ssl_stream *);
+static int interpret_ssl_error(const char *function, int ret, int error,
+ int *want);
+static DH *tmp_dh_callback(SSL *ssl, int is_export UNUSED, int keylength);
+static void log_ca_cert(const char *file_name, X509 *cert);
+
+static short int
+want_to_poll_events(int want)
+{
+ switch (want) {
+ case SSL_NOTHING:
+ NOT_REACHED();
+
+ case SSL_READING:
+ return POLLIN;
+
+ case SSL_WRITING:
+ return POLLOUT;
+
+ default:
+ NOT_REACHED();
+ }
+}
+
+static int
+new_ssl_stream(const char *name, int fd, enum session_type type,
+ enum ssl_state state, const struct sockaddr_in *remote,
+ struct stream **streamp)
+{
+ struct sockaddr_in local;
+ socklen_t local_len = sizeof local;
+ struct ssl_stream *sslv;
+ SSL *ssl = NULL;
+ int on = 1;
+ int retval;
+
+ /* Check for all the needful configuration. */
+ retval = 0;
+ if (!has_private_key) {
+ VLOG_ERR("Private key must be configured to use SSL");
+ retval = ENOPROTOOPT;
+ }
+ if (!has_certificate) {
+ VLOG_ERR("Certificate must be configured to use SSL");
+ retval = ENOPROTOOPT;
+ }
+ if (!has_ca_cert && !bootstrap_ca_cert) {
+ VLOG_ERR("CA certificate must be configured to use SSL");
+ retval = ENOPROTOOPT;
+ }
+ if (!SSL_CTX_check_private_key(ctx)) {
+ VLOG_ERR("Private key does not match certificate public key: %s",
+ ERR_error_string(ERR_get_error(), NULL));
+ retval = ENOPROTOOPT;
+ }
+ if (retval) {
+ goto error;
+ }
+
+ /* Get the local IP and port information */
+ retval = getsockname(fd, (struct sockaddr *) &local, &local_len);
+ if (retval) {
+ memset(&local, 0, sizeof local);
+ }
+
+ /* Disable Nagle. */
+ retval = setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &on, sizeof on);
+ if (retval) {
+ VLOG_ERR("%s: setsockopt(TCP_NODELAY): %s", name, strerror(errno));
+ retval = errno;
+ goto error;
+ }
+
+ /* Create and configure OpenSSL stream. */
+ ssl = SSL_new(ctx);
+ if (ssl == NULL) {
+ VLOG_ERR("SSL_new: %s", ERR_error_string(ERR_get_error(), NULL));
+ retval = ENOPROTOOPT;
+ goto error;
+ }
+ if (SSL_set_fd(ssl, fd) == 0) {
+ VLOG_ERR("SSL_set_fd: %s", ERR_error_string(ERR_get_error(), NULL));
+ retval = ENOPROTOOPT;
+ goto error;
+ }
+ if (bootstrap_ca_cert && type == CLIENT) {
+ SSL_set_verify(ssl, SSL_VERIFY_NONE, NULL);
+ }
+
+ /* Create and return the ssl_stream. */
+ sslv = xmalloc(sizeof *sslv);
+ stream_init(&sslv->stream, &ssl_stream_class, EAGAIN, name);
+ stream_set_remote_ip(&sslv->stream, remote->sin_addr.s_addr);
+ stream_set_remote_port(&sslv->stream, remote->sin_port);
+ stream_set_local_ip(&sslv->stream, local.sin_addr.s_addr);
+ stream_set_local_port(&sslv->stream, local.sin_port);
+ sslv->state = state;
+ sslv->type = type;
+ sslv->fd = fd;
+ sslv->ssl = ssl;
+ sslv->txbuf = NULL;
+ sslv->rx_want = sslv->tx_want = SSL_NOTHING;
+ *streamp = &sslv->stream;
+ return 0;
+
+error:
+ if (ssl) {
+ SSL_free(ssl);
+ }
+ close(fd);
+ return retval;
+}
+
+static struct ssl_stream *
+ssl_stream_cast(struct stream *stream)
+{
+ stream_assert_class(stream, &ssl_stream_class);
+ return CONTAINER_OF(stream, struct ssl_stream, stream);
+}
+
+static int
+ssl_open(const char *name, char *suffix, struct stream **streamp)
+{
+ struct sockaddr_in sin;
+ int error, fd;
+
+ error = ssl_init();
+ if (error) {
+ return error;
+ }
+
+ error = inet_open_active(SOCK_STREAM, suffix, OFP_SSL_PORT, &sin, &fd);
+ if (fd >= 0) {
+ int state = error ? STATE_TCP_CONNECTING : STATE_SSL_CONNECTING;
+ return new_ssl_stream(name, fd, CLIENT, state, &sin, streamp);
+ } else {
+ VLOG_ERR("%s: connect: %s", name, strerror(error));
+ return error;
+ }
+}
+
+static int
+do_ca_cert_bootstrap(struct stream *stream)
+{
+ struct ssl_stream *sslv = ssl_stream_cast(stream);
+ STACK_OF(X509) *chain;
+ X509 *ca_cert;
+ FILE *file;
+ int error;
+ int fd;
+
+ chain = SSL_get_peer_cert_chain(sslv->ssl);
+ if (!chain || !sk_X509_num(chain)) {
+ VLOG_ERR("could not bootstrap CA cert: no certificate presented by "
+ "peer");
+ return EPROTO;
+ }
+ ca_cert = sk_X509_value(chain, sk_X509_num(chain) - 1);
+
+ /* Check that 'ca_cert' is self-signed. Otherwise it is not a CA
+ * certificate and we should not attempt to use it as one. */
+ error = X509_check_issued(ca_cert, ca_cert);
+ if (error) {
+ VLOG_ERR("could not bootstrap CA cert: obtained certificate is "
+ "not self-signed (%s)",
+ X509_verify_cert_error_string(error));
+ if (sk_X509_num(chain) < 2) {
+ VLOG_ERR("only one certificate was received, so probably the peer "
+ "is not configured to send its CA certificate");
+ }
+ return EPROTO;
+ }
+
+ fd = open(ca_cert_file, O_CREAT | O_EXCL | O_WRONLY, 0444);
+ if (fd < 0) {
+ VLOG_ERR("could not bootstrap CA cert: creating %s failed: %s",
+ ca_cert_file, strerror(errno));
+ return errno;
+ }
+
+ file = fdopen(fd, "w");
+ if (!file) {
+ int error = errno;
+ VLOG_ERR("could not bootstrap CA cert: fdopen failed: %s",
+ strerror(error));
+ unlink(ca_cert_file);
+ return error;
+ }
+
+ if (!PEM_write_X509(file, ca_cert)) {
+ VLOG_ERR("could not bootstrap CA cert: PEM_write_X509 to %s failed: "
+ "%s", ca_cert_file, ERR_error_string(ERR_get_error(), NULL));
+ fclose(file);
+ unlink(ca_cert_file);
+ return EIO;
+ }
+
+ if (fclose(file)) {
+ int error = errno;
+ VLOG_ERR("could not bootstrap CA cert: writing %s failed: %s",
+ ca_cert_file, strerror(error));
+ unlink(ca_cert_file);
+ return error;
+ }
+
+ VLOG_INFO("successfully bootstrapped CA cert to %s", ca_cert_file);
+ log_ca_cert(ca_cert_file, ca_cert);
+ bootstrap_ca_cert = false;
+ has_ca_cert = true;
+
+ /* SSL_CTX_add_client_CA makes a copy of ca_cert's relevant data. */
+ SSL_CTX_add_client_CA(ctx, ca_cert);
+
+ /* SSL_CTX_use_certificate() takes ownership of the certificate passed in.
+ * 'ca_cert' is owned by sslv->ssl, so we need to duplicate it. */
+ ca_cert = X509_dup(ca_cert);
+ if (!ca_cert) {
+ out_of_memory();
+ }
+ if (SSL_CTX_load_verify_locations(ctx, ca_cert_file, NULL) != 1) {
+ VLOG_ERR("SSL_CTX_load_verify_locations: %s",
+ ERR_error_string(ERR_get_error(), NULL));
+ return EPROTO;
+ }
+ VLOG_INFO("killing successful connection to retry using CA cert");
+ return EPROTO;
+}
+
+static int
+ssl_connect(struct stream *stream)
+{
+ struct ssl_stream *sslv = ssl_stream_cast(stream);
+ int retval;
+
+ switch (sslv->state) {
+ case STATE_TCP_CONNECTING:
+ retval = check_connection_completion(sslv->fd);
+ if (retval) {
+ return retval;
+ }
+ sslv->state = STATE_SSL_CONNECTING;
+ /* Fall through. */
+
+ case STATE_SSL_CONNECTING:
+ retval = (sslv->type == CLIENT
+ ? SSL_connect(sslv->ssl) : SSL_accept(sslv->ssl));
+ if (retval != 1) {
+ int error = SSL_get_error(sslv->ssl, retval);
+ if (retval < 0 && ssl_wants_io(error)) {
+ return EAGAIN;
+ } else {
+ int unused;
+ interpret_ssl_error((sslv->type == CLIENT ? "SSL_connect"
+ : "SSL_accept"), retval, error, &unused);
+ shutdown(sslv->fd, SHUT_RDWR);
+ return EPROTO;
+ }
+ } else if (bootstrap_ca_cert) {
+ return do_ca_cert_bootstrap(stream);
+ } else if ((SSL_get_verify_mode(sslv->ssl)
+ & (SSL_VERIFY_NONE | SSL_VERIFY_PEER))
+ != SSL_VERIFY_PEER) {
+ /* Two or more SSL connections completed at the same time while we
+ * were in bootstrap mode. Only one of these can finish the
+ * bootstrap successfully. The other one(s) must be rejected
+ * because they were not verified against the bootstrapped CA
+ * certificate. (Alternatively we could verify them against the CA
+ * certificate, but that's more trouble than it's worth. These
+ * connections will succeed the next time they retry, assuming that
+ * they have a certificate against the correct CA.) */
+ VLOG_ERR("rejecting SSL connection during bootstrap race window");
+ return EPROTO;
+ } else {
+ return 0;
+ }
+ }
+
+ NOT_REACHED();
+}
+
+static void
+ssl_close(struct stream *stream)
+{
+ struct ssl_stream *sslv = ssl_stream_cast(stream);
+ ssl_clear_txbuf(sslv);
+ SSL_free(sslv->ssl);
+ close(sslv->fd);
+ free(sslv);
+}
+
+static int
+interpret_ssl_error(const char *function, int ret, int error,
+ int *want)
+{
+ *want = SSL_NOTHING;
+
+ switch (error) {
+ case SSL_ERROR_NONE:
+ VLOG_ERR_RL(&rl, "%s: unexpected SSL_ERROR_NONE", function);
+ break;
+
+ case SSL_ERROR_ZERO_RETURN:
+ VLOG_ERR_RL(&rl, "%s: unexpected SSL_ERROR_ZERO_RETURN", function);
+ break;
+
+ case SSL_ERROR_WANT_READ:
+ *want = SSL_READING;
+ return EAGAIN;
+
+ case SSL_ERROR_WANT_WRITE:
+ *want = SSL_WRITING;
+ return EAGAIN;
+
+ case SSL_ERROR_WANT_CONNECT:
+ VLOG_ERR_RL(&rl, "%s: unexpected SSL_ERROR_WANT_CONNECT", function);
+ break;
+
+ case SSL_ERROR_WANT_ACCEPT:
+ VLOG_ERR_RL(&rl, "%s: unexpected SSL_ERROR_WANT_ACCEPT", function);
+ break;
+
+ case SSL_ERROR_WANT_X509_LOOKUP:
+ VLOG_ERR_RL(&rl, "%s: unexpected SSL_ERROR_WANT_X509_LOOKUP",
+ function);
+ break;
+
+ case SSL_ERROR_SYSCALL: {
+ int queued_error = ERR_get_error();
+ if (queued_error == 0) {
+ if (ret < 0) {
+ int status = errno;
+ VLOG_WARN_RL(&rl, "%s: system error (%s)",
+ function, strerror(status));
+ return status;
+ } else {
+ VLOG_WARN_RL(&rl, "%s: unexpected SSL connection close",
+ function);
+ return EPROTO;
+ }
+ } else {
+ VLOG_WARN_RL(&rl, "%s: %s",
+ function, ERR_error_string(queued_error, NULL));
+ break;
+ }
+ }
+
+ case SSL_ERROR_SSL: {
+ int queued_error = ERR_get_error();
+ if (queued_error != 0) {
+ VLOG_WARN_RL(&rl, "%s: %s",
+ function, ERR_error_string(queued_error, NULL));
+ } else {
+ VLOG_ERR_RL(&rl, "%s: SSL_ERROR_SSL without queued error",
+ function);
+ }
+ break;
+ }
+
+ default:
+ VLOG_ERR_RL(&rl, "%s: bad SSL error code %d", function, error);
+ break;
+ }
+ return EIO;
+}
+
+static ssize_t
+ssl_recv(struct stream *stream, void *buffer, size_t n)
+{
+ struct ssl_stream *sslv = ssl_stream_cast(stream);
+ int old_state;
+ ssize_t ret;
+
+ /* Behavior of zero-byte SSL_read is poorly defined. */
+ assert(n > 0);
+
+ old_state = SSL_get_state(sslv->ssl);
+ ret = SSL_read(sslv->ssl, buffer, n);
+ if (old_state != SSL_get_state(sslv->ssl)) {
+ sslv->tx_want = SSL_NOTHING;
+ }
+ sslv->rx_want = SSL_NOTHING;
+
+ if (ret > 0) {
+ return ret;
+ } else {
+ int error = SSL_get_error(sslv->ssl, ret);
+ if (error == SSL_ERROR_ZERO_RETURN) {
+ return 0;
+ } else {
+ return interpret_ssl_error("SSL_read", ret, error, &sslv->rx_want);
+ }
+ }
+}
+
+static void
+ssl_clear_txbuf(struct ssl_stream *sslv)
+{
+ ofpbuf_delete(sslv->txbuf);
+ sslv->txbuf = NULL;
+}
+
+static int
+ssl_do_tx(struct stream *stream)
+{
+ struct ssl_stream *sslv = ssl_stream_cast(stream);
+
+ for (;;) {
+ int old_state = SSL_get_state(sslv->ssl);
+ int ret = SSL_write(sslv->ssl, sslv->txbuf->data, sslv->txbuf->size);
+ if (old_state != SSL_get_state(sslv->ssl)) {
+ sslv->rx_want = SSL_NOTHING;
+ }
+ sslv->tx_want = SSL_NOTHING;
+ if (ret > 0) {
+ ofpbuf_pull(sslv->txbuf, ret);
+ if (sslv->txbuf->size == 0) {
+ return 0;
+ }
+ } else {
+ int ssl_error = SSL_get_error(sslv->ssl, ret);
+ if (ssl_error == SSL_ERROR_ZERO_RETURN) {
+ VLOG_WARN_RL(&rl, "SSL_write: connection closed");
+ return EPIPE;
+ } else {
+ return interpret_ssl_error("SSL_write", ret, ssl_error,
+ &sslv->tx_want);
+ }
+ }
+ }
+}
+
+static ssize_t
+ssl_send(struct stream *stream, const void *buffer, size_t n)
+{
+ struct ssl_stream *sslv = ssl_stream_cast(stream);
+
+ if (sslv->txbuf) {
+ return EAGAIN;
+ } else {
+ int error;
+
+ sslv->txbuf = ofpbuf_clone_data(buffer, n);
+ error = ssl_do_tx(stream);
+ switch (error) {
+ case 0:
+ ssl_clear_txbuf(sslv);
+ return 0;
+ case EAGAIN:
+ leak_checker_claim(buffer);
+ return 0;
+ default:
+ sslv->txbuf = NULL;
+ return error;
+ }
+ }
+}
+
+static void
+ssl_run(struct stream *stream)
+{
+ struct ssl_stream *sslv = ssl_stream_cast(stream);
+
+ if (sslv->txbuf && ssl_do_tx(stream) != EAGAIN) {
+ ssl_clear_txbuf(sslv);
+ }
+}
+
+static void
+ssl_run_wait(struct stream *stream)
+{
+ struct ssl_stream *sslv = ssl_stream_cast(stream);
+
+ if (sslv->tx_want != SSL_NOTHING) {
+ poll_fd_wait(sslv->fd, want_to_poll_events(sslv->tx_want));
+ }
+}
+
+static void
+ssl_wait(struct stream *stream, enum stream_wait_type wait)
+{
+ struct ssl_stream *sslv = ssl_stream_cast(stream);
+
+ switch (wait) {
+ case STREAM_CONNECT:
+ if (stream_connect(stream) != EAGAIN) {
+ poll_immediate_wake();
+ } else {
+ switch (sslv->state) {
+ case STATE_TCP_CONNECTING:
+ poll_fd_wait(sslv->fd, POLLOUT);
+ break;
+
+ case STATE_SSL_CONNECTING:
+ /* ssl_connect() called SSL_accept() or SSL_connect(), which
+ * set up the status that we test here. */
+ poll_fd_wait(sslv->fd,
+ want_to_poll_events(SSL_want(sslv->ssl)));
+ break;
+
+ default:
+ NOT_REACHED();
+ }
+ }
+ break;
+
+ case STREAM_RECV:
+ if (sslv->rx_want != SSL_NOTHING) {
+ poll_fd_wait(sslv->fd, want_to_poll_events(sslv->rx_want));
+ } else {
+ poll_immediate_wake();
+ }
+ break;
+
+ case STREAM_SEND:
+ if (!sslv->txbuf) {
+ /* We have room in our tx queue. */
+ poll_immediate_wake();
+ } else {
+ /* stream_run_wait() will do the right thing; don't bother with
+ * redundancy. */
+ }
+ break;
+
+ default:
+ NOT_REACHED();
+ }
+}
+
+struct stream_class ssl_stream_class = {
+ "ssl", /* name */
+ ssl_open, /* open */
+ ssl_close, /* close */
+ ssl_connect, /* connect */
+ ssl_recv, /* recv */
+ ssl_send, /* send */
+ ssl_run, /* run */
+ ssl_run_wait, /* run_wait */
+ ssl_wait, /* wait */
+};
+\f
+/* Passive SSL. */
+
+struct pssl_pstream
+{
+ struct pstream pstream;
+ int fd;
+};
+
+struct pstream_class pssl_pstream_class;
+
+static struct pssl_pstream *
+pssl_pstream_cast(struct pstream *pstream)
+{
+ pstream_assert_class(pstream, &pssl_pstream_class);
+ return CONTAINER_OF(pstream, struct pssl_pstream, pstream);
+}
+
+static int
+pssl_open(const char *name, char *suffix, struct pstream **pstreamp)
+{
+ struct pssl_pstream *pssl;
+ int retval;
+ int fd;
+
+ retval = ssl_init();
+ if (retval) {
+ return retval;
+ }
+
+ fd = inet_open_passive(SOCK_STREAM, suffix, OFP_SSL_PORT);
+ if (fd < 0) {
+ return -fd;
+ }
+
+ pssl = xmalloc(sizeof *pssl);
+ pstream_init(&pssl->pstream, &pssl_pstream_class, name);
+ pssl->fd = fd;
+ *pstreamp = &pssl->pstream;
+ return 0;
+}
+
+static void
+pssl_close(struct pstream *pstream)
+{
+ struct pssl_pstream *pssl = pssl_pstream_cast(pstream);
+ close(pssl->fd);
+ free(pssl);
+}
+
+static int
+pssl_accept(struct pstream *pstream, struct stream **new_streamp)
+{
+ struct pssl_pstream *pssl = pssl_pstream_cast(pstream);
+ struct sockaddr_in sin;
+ socklen_t sin_len = sizeof sin;
+ char name[128];
+ int new_fd;
+ int error;
+
+ new_fd = accept(pssl->fd, &sin, &sin_len);
+ if (new_fd < 0) {
+ int error = errno;
+ if (error != EAGAIN) {
+ VLOG_DBG_RL(&rl, "accept: %s", strerror(error));
+ }
+ return error;
+ }
+
+ error = set_nonblocking(new_fd);
+ if (error) {
+ close(new_fd);
+ return error;
+ }
+
+ sprintf(name, "ssl:"IP_FMT, IP_ARGS(&sin.sin_addr));
+ if (sin.sin_port != htons(OFP_SSL_PORT)) {
+ sprintf(strchr(name, '\0'), ":%"PRIu16, ntohs(sin.sin_port));
+ }
+ return new_ssl_stream(name, new_fd, SERVER, STATE_SSL_CONNECTING, &sin,
+ new_streamp);
+}
+
+static void
+pssl_wait(struct pstream *pstream)
+{
+ struct pssl_pstream *pssl = pssl_pstream_cast(pstream);
+ poll_fd_wait(pssl->fd, POLLIN);
+}
+
+struct pstream_class pssl_pstream_class = {
+ "pssl",
+ pssl_open,
+ pssl_close,
+ pssl_accept,
+ pssl_wait,
+};
+\f
+/*
+ * Returns true if OpenSSL error is WANT_READ or WANT_WRITE, indicating that
+ * OpenSSL is requesting that we call it back when the socket is ready for read
+ * or writing, respectively.
+ */
+static bool
+ssl_wants_io(int ssl_error)
+{
+ return (ssl_error == SSL_ERROR_WANT_WRITE
+ || ssl_error == SSL_ERROR_WANT_READ);
+}
+
+static int
+ssl_init(void)
+{
+ static int init_status = -1;
+ if (init_status < 0) {
+ init_status = do_ssl_init();
+ assert(init_status >= 0);
+ }
+ return init_status;
+}
+
+static int
+do_ssl_init(void)
+{
+ SSL_METHOD *method;
+
+ SSL_library_init();
+ SSL_load_error_strings();
+
+ method = TLSv1_method();
+ if (method == NULL) {
+ VLOG_ERR("TLSv1_method: %s", ERR_error_string(ERR_get_error(), NULL));
+ return ENOPROTOOPT;
+ }
+
+ ctx = SSL_CTX_new(method);
+ if (ctx == NULL) {
+ VLOG_ERR("SSL_CTX_new: %s", ERR_error_string(ERR_get_error(), NULL));
+ return ENOPROTOOPT;
+ }
+ SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3);
+ SSL_CTX_set_tmp_dh_callback(ctx, tmp_dh_callback);
+ SSL_CTX_set_mode(ctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
+ SSL_CTX_set_mode(ctx, SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
+ SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT,
+ NULL);
+
+ return 0;
+}
+
+static DH *
+tmp_dh_callback(SSL *ssl UNUSED, int is_export UNUSED, int keylength)
+{
+ struct dh {
+ int keylength;
+ DH *dh;
+ DH *(*constructor)(void);
+ };
+
+ static struct dh dh_table[] = {
+ {1024, NULL, get_dh1024},
+ {2048, NULL, get_dh2048},
+ {4096, NULL, get_dh4096},
+ };
+
+ struct dh *dh;
+
+ for (dh = dh_table; dh < &dh_table[ARRAY_SIZE(dh_table)]; dh++) {
+ if (dh->keylength == keylength) {
+ if (!dh->dh) {
+ dh->dh = dh->constructor();
+ if (!dh->dh) {
+ ovs_fatal(ENOMEM, "out of memory constructing "
+ "Diffie-Hellman parameters");
+ }
+ }
+ return dh->dh;
+ }
+ }
+ VLOG_ERR_RL(&rl, "no Diffie-Hellman parameters for key length %d",
+ keylength);
+ return NULL;
+}
+
+/* Returns true if SSL is at least partially configured. */
+bool
+stream_ssl_is_configured(void)
+{
+ return has_private_key || has_certificate || has_ca_cert;
+}
+
+void
+stream_ssl_set_private_key_file(const char *file_name)
+{
+ if (ssl_init()) {
+ return;
+ }
+ if (SSL_CTX_use_PrivateKey_file(ctx, file_name, SSL_FILETYPE_PEM) != 1) {
+ VLOG_ERR("SSL_use_PrivateKey_file: %s",
+ ERR_error_string(ERR_get_error(), NULL));
+ return;
+ }
+ has_private_key = true;
+}
+
+void
+stream_ssl_set_certificate_file(const char *file_name)
+{
+ if (ssl_init()) {
+ return;
+ }
+ if (SSL_CTX_use_certificate_chain_file(ctx, file_name) != 1) {
+ VLOG_ERR("SSL_use_certificate_file: %s",
+ ERR_error_string(ERR_get_error(), NULL));
+ return;
+ }
+ has_certificate = true;
+}
+
+/* Reads the X509 certificate or certificates in file 'file_name'. On success,
+ * stores the address of the first element in an array of pointers to
+ * certificates in '*certs' and the number of certificates in the array in
+ * '*n_certs', and returns 0. On failure, stores a null pointer in '*certs', 0
+ * in '*n_certs', and returns a positive errno value.
+ *
+ * The caller is responsible for freeing '*certs'. */
+static int
+read_cert_file(const char *file_name, X509 ***certs, size_t *n_certs)
+{
+ FILE *file;
+ size_t allocated_certs = 0;
+
+ *certs = NULL;
+ *n_certs = 0;
+
+ file = fopen(file_name, "r");
+ if (!file) {
+ VLOG_ERR("failed to open %s for reading: %s",
+ file_name, strerror(errno));
+ return errno;
+ }
+
+ for (;;) {
+ X509 *certificate;
+ int c;
+
+ /* Read certificate from file. */
+ certificate = PEM_read_X509(file, NULL, NULL, NULL);
+ if (!certificate) {
+ size_t i;
+
+ VLOG_ERR("PEM_read_X509 failed reading %s: %s",
+ file_name, ERR_error_string(ERR_get_error(), NULL));
+ for (i = 0; i < *n_certs; i++) {
+ X509_free((*certs)[i]);
+ }
+ free(*certs);
+ *certs = NULL;
+ *n_certs = 0;
+ return EIO;
+ }
+
+ /* Add certificate to array. */
+ if (*n_certs >= allocated_certs) {
+ *certs = x2nrealloc(*certs, &allocated_certs, sizeof **certs);
+ }
+ (*certs)[(*n_certs)++] = certificate;
+
+ /* Are there additional certificates in the file? */
+ do {
+ c = getc(file);
+ } while (isspace(c));
+ if (c == EOF) {
+ break;
+ }
+ ungetc(c, file);
+ }
+ fclose(file);
+ return 0;
+}
+
+
+/* Sets 'file_name' as the name of a file containing one or more X509
+ * certificates to send to the peer. Typical use in OpenFlow is to send the CA
+ * certificate to the peer, which enables a switch to pick up the controller's
+ * CA certificate on its first connection. */
+void
+stream_ssl_set_peer_ca_cert_file(const char *file_name)
+{
+ X509 **certs;
+ size_t n_certs;
+ size_t i;
+
+ if (ssl_init()) {
+ return;
+ }
+
+ if (!read_cert_file(file_name, &certs, &n_certs)) {
+ for (i = 0; i < n_certs; i++) {
+ if (SSL_CTX_add_extra_chain_cert(ctx, certs[i]) != 1) {
+ VLOG_ERR("SSL_CTX_add_extra_chain_cert: %s",
+ ERR_error_string(ERR_get_error(), NULL));
+ }
+ }
+ free(certs);
+ }
+}
+
+/* Logs fingerprint of CA certificate 'cert' obtained from 'file_name'. */
+static void
+log_ca_cert(const char *file_name, X509 *cert)
+{
+ unsigned char digest[EVP_MAX_MD_SIZE];
+ unsigned int n_bytes;
+ struct ds fp;
+ char *subject;
+
+ ds_init(&fp);
+ if (!X509_digest(cert, EVP_sha1(), digest, &n_bytes)) {
+ ds_put_cstr(&fp, "<out of memory>");
+ } else {
+ unsigned int i;
+ for (i = 0; i < n_bytes; i++) {
+ if (i) {
+ ds_put_char(&fp, ':');
+ }
+ ds_put_format(&fp, "%02hhx", digest[i]);
+ }
+ }
+ subject = X509_NAME_oneline(X509_get_subject_name(cert), NULL, 0);
+ VLOG_INFO("Trusting CA cert from %s (%s) (fingerprint %s)", file_name,
+ subject ? subject : "<out of memory>", ds_cstr(&fp));
+ free(subject);
+ ds_destroy(&fp);
+}
+
+/* Sets 'file_name' as the name of the file from which to read the CA
+ * certificate used to verify the peer within SSL connections. If 'bootstrap'
+ * is false, the file must exist. If 'bootstrap' is false, then the file is
+ * read if it is exists; if it does not, then it will be created from the CA
+ * certificate received from the peer on the first SSL connection. */
+void
+stream_ssl_set_ca_cert_file(const char *file_name, bool bootstrap)
+{
+ X509 **certs;
+ size_t n_certs;
+ struct stat s;
+
+ if (ssl_init()) {
+ return;
+ }
+
+ if (bootstrap && stat(file_name, &s) && errno == ENOENT) {
+ bootstrap_ca_cert = true;
+ ca_cert_file = xstrdup(file_name);
+ } else if (!read_cert_file(file_name, &certs, &n_certs)) {
+ size_t i;
+
+ /* Set up list of CAs that the server will accept from the client. */
+ for (i = 0; i < n_certs; i++) {
+ /* SSL_CTX_add_client_CA makes a copy of the relevant data. */
+ if (SSL_CTX_add_client_CA(ctx, certs[i]) != 1) {
+ VLOG_ERR("failed to add client certificate %d from %s: %s",
+ i, file_name,
+ ERR_error_string(ERR_get_error(), NULL));
+ } else {
+ log_ca_cert(file_name, certs[i]);
+ }
+ X509_free(certs[i]);
+ }
+
+ /* Set up CAs for OpenSSL to trust in verifying the peer's
+ * certificate. */
+ if (SSL_CTX_load_verify_locations(ctx, file_name, NULL) != 1) {
+ VLOG_ERR("SSL_CTX_load_verify_locations: %s",
+ ERR_error_string(ERR_get_error(), NULL));
+ return;
+ }
+
+ has_ca_cert = true;
+ }
+}
projects / openvswitch / commitdiff